462 research outputs found
Building lighting energy consumption modelling with hybrid neural-statistic approaches
"In the proposed work we aim at modelling building lighting energy consumption. We compared several classical methods to the latest Artificial Intelligence. modelling technique: Artificial Neural Networks Ensembling (ANNE). Therefore, in this study we show how we built the ANNE and a new hybrid model based on the. statistical-ANNE combination. Experimentation has been carried out over a three. months data set coming from a real office building located in the ENEA ‘Casaccia’. Research Centre. Experimental results show that the proposed hybrid statistical-ANNE approach can get a remarkable improvement with respect to the best classical method(the statistical one).
EXPERIMENTAL DETERMINATION OF LAMINAR BURNING VELOCITY OF BIOGAS AT PRESSURES UP TO 5 BAR
This paper presents a very detailed description of a new cylindrical constant volume combustion chamber designed for laminar burning velocity determination of gaseous mixtures at ambient temperature and initial pressure up to 6 bar. The experimental setup, the experimental procedure and the determination of the range of flame radius for laminar burning determination are all described in details. The laminar burning velocity of twelve synthetic biogas mixtures has been studied. Initial pressure varying between 1 and 5 bar, equivalence ratios, f, between 0.7 and 1.1 and percentage dilution, with a mixture of CO2 and N2, between 35 and 55% have been considered. Five experiments were run for each mixture providing a maximum percentage standard deviation of 8.11%. However, for two third of the mixtures this value is lower than 3.55%. A comparison with simulation using PREMIX for both GRI-Mech 3.0 and San Diego mechanisms has provided closer agreement for mixtures with equivalence ratio closer to stoichiometry whereas for f = 0.7 the deviation is larger than 15% for all pressures. Mixtures with lower equivalence ratio, higher dilution percentage and higher initial pressure presents the lower values of laminar burning velocity
Rapid detection of copy number variations and point mutations in BRCA1/2 genes using a single workflow by ion semiconductor sequencing pipeline
Molecular analysis of BRCA1 (MIM# 604370) and BRCA2 (MIM #600185) genes is essential for familial breast and ovarian cancer prevention and treatment. An efficient, rapid, cost-effective accurate strategy for the detection of pathogenic variants is crucial. Mutations detection of BRCA1/2 genes includes screening for single nucleotide variants (SNVs), small insertions or deletions (indels), and Copy Number Variations (CNVs). Sanger sequencing is unable to identify CNVs and therefore Multiplex Ligation Probe amplification (MLPA) or Multiplex Amplicon Quantification (MAQ) is used to complete the BRCA1/2 genes analysis. The rapid evolution of Next Generation Sequencing (NGS) technologies allows the search for point mutations and CNVs with a single platform and workflow. In this study we test the possibilities of NGS technology to simultaneously detect point mutations and CNVs in BRCA1/2 genes, using the OncomineTM BRCA Research Assay on Personal Genome Machine (PGM) Platform with Ion Reporter Software for sequencing data analysis (Thermo Fisher Scientific). Comparison between the NGS-CNVs, MLPA and MAQ results shows how the NGS approach is the most complete and fast method for the simultaneous detection of all BRCA mutations, avoiding the usual time consuming multistep approach in the routine diagnostic testing of hereditary breast and ovarian cancers
Molecular analysis of sarcomeric and non-sarcomeric genes in patients with hypertrophic cardiomyopathy.
Background: Hypertrophic cardiomyopathy (HCM) is a common genetic heart disorder characterized by
unexplained left ventricle hypertrophy associated with non-dilated ventricular chambers. Several genes
encoding heart sarcomeric proteins have been associated to HCM, but a small proportion of HCM patients
harbor alterations in other non-sarcomeric loci. The variable expression of HCM seems influenced by genetic
modifier factors and new sequencing technologies are redefining the understanding of genotype–phenotype
relationships, even if the interpretations of the numerous identified variants pose several challenges.
Methods and results: We investigated 62 sarcomeric and non-sarcomeric genes in 41 HCM cases and in
3 HCM-related disorders patients. We employed an integrated approach that combines multiple tools for
the prediction, annotation and visualization of functional variants. Genotype–phenotype correlations
were carried out for inspecting the involvement of each gene in age onset and clinical variability of HCM. The
80% of the non-syndromic patients showed at least one rare non-synonymous variant (nsSNV) and among
them, 58% carried alterations in sarcomeric loci, 14% in desmosomal and 7% in other non-sarcomeric ones
without any sarcomere change. Statistical analyses revealed an inverse correlation between the number of
nsSNVs and age at onset, and a relationship between the clinical variability and number and type of variants.
Conclusions: Our results extend the mutational spectrum of HCM and contribute in defining the molecular
pathogenesis and inheritance pattern(s) of this condition. Besides, we delineate a specific procedure for the
identification of the most likely pathogenetic variants for a next generation sequencing approach embodied in
a clinical context
CLASH-VLT: Testing the Nature of Gravity with Galaxy Cluster Mass Profiles
We use high-precision kinematic and lensing measurements of the total mass
profile of the dynamically relaxed galaxy cluster MACS J1206.2-0847 at
to estimate the value of the ratio between the two scalar
potentials in the linear perturbed Friedmann-Lemaitre-Robertson-Walker
metric.[...] Complementary kinematic and lensing mass profiles were derived
from exhaustive analyses using the data from the Cluster Lensing And Supernova
survey with Hubble (CLASH) and the spectroscopic follow-up with the Very Large
Telescope (CLASH-VLT). Whereas the kinematic mass profile tracks only the
time-time part of the perturbed metric (i.e. only ), the lensing mass
profile reflects the contribution of both time-time and space-space components
(i.e. the sum ). We thus express as a function of the mass
profiles and perform our analysis over the radial range . Using a spherical Navarro-Frenk-White mass profile, which
well fits the data, we obtain \eta(r_{200})=1.01\,_{-0.28}^{+0.31} at the
68\% C.L. We discuss the effect of assuming different functional forms for mass
profiles and of the orbit anisotropy in the kinematic reconstruction.
Interpreting this result within the well-studied modified gravity model,
the constraint on translates into an upper bound to the interaction
length (inverse of the scalaron mass) smaller than 2 Mpc. This tight constraint
on the interaction range is however substantially relaxed when
systematic uncertainties in the analysis are considered. Our analysis
highlights the potential of this method to detect deviations from general
relativity, while calling for the need of further high-quality data on the
total mass distribution of clusters and improved control on systematic effects.Comment: 18 pages, 3 figures, submitted to JCA
Triple positive breast cancer. A distinct subtype?
Breast cancer is a heterogeneous disease, and within the HER-2 positive subtype this is highly exemplified by the presence of substantial phenotypical and clinical heterogeneity, mostly related to hormonal receptor (HR) expression. It is well known how HER-2 positivity is commonly associated with a more aggressive tumor phenotype and decreased overall survival and, moreover, with a reduced benefit from endocrine treatment. Preclinical studies corroborate the role played by functional crosstalks between HER-2 and estrogen receptor (ER) signaling in endocrine resistance and, more recently, the activation of ER signaling is emerging as a possible mechanism of resistance to HER-2 blocking agents. Indeed, HER-2 positive breast cancer heterogeneity has been suggested to underlie the variability of response not only to endocrine treatments, but also to HER-2 blocking agents. Among HER-2 positive tumors, HR status probably defines two distinct subtypes, with dissimilar clinical behavior and different sensitivity to anticancer agents. The triple positive subtype, namely, ER/PgR/Her-2 positive tumors, could be considered the subset which most closely resembles the HER-2 negative/HR positive tumors, with substantial differences in biology and clinical outcome. We argue on whether in this subgroup the "standard" treatment may be considered, in selected cases, i.e., small tumors, low tumor burden, high expression of both hormonal receptors, an overtreatment. This article review the existing literature on biologic and clinical data concerning the HER-2/ER/PgR positive tumors, in an attempt to better define the HER-2 subtypes and to optimize the use of HER-2 targeted agents, chemotherapy and endocrine treatments in the various subsets
Cytochalasin B Influences Cytoskeletal Organization and Osteogenic Potential of Human Wharton's Jelly Mesenchymal Stem Cells
Among perinatal stem cells of the umbilical cord, human Wharton's jelly mesenchymal stem cells (hWJ-MSCs) are of great interest for cell-based therapy approaches in regenerative medicine, showing some advantages over other MSCs. In fact, hWJ-MSCs, placed between embryonic and adult MSCs, are not tumorigenic and are harvested with few ethical concerns. Furthermore, these cells can be easily cultured in vitro, maintaining both stem properties and a high proliferative rate for several passages, as well as trilineage capacity of differentiation. Recently, it has been demonstrated that cytoskeletal organization influences stem cell biology. Among molecules able to modulate its dynamics, Cytochalasin B (CB), a cyto-permeable mycotoxin, influences actin microfilament polymerization, thus affecting several cell properties, such as the ability of MSCs to differentiate towards a specific commitment. Here, we investigated for the first time the effects of a 24 h-treatment with CB at different concentrations (0.1-3 mu M) on hWJ-MSCs. CB influenced the cytoskeletal organization in a dose-dependent manner, inducing changes in cell number, proliferation, shape, and nanomechanical properties, thus promoting the osteogenic commitment of hWJ-MSCs, as confirmed by the expression analysis of osteogenic/autophagy markers
CLASH-VLT: The inner slope of the MACS J1206.2-0847 mass density profile
The inner slope gammaDM of the dark matter (DM) density profile of
cosmological halos carries information about the properties of DM and/or
baryonic processes affecting the halo gravitational potential. Cold DM
cosmological simulations predict steep inner slopes, gammaDM>~1. We test this
prediction on the MACS J1206.2-0847 cluster at redshift z=0.44, whose DM
density profile was claimed to be cored at the center. We determine the cluster
DM density profile from 2 kpc from the cluster center to the virial radius (~2
Mpc), using the velocity distribution of ~500 cluster galaxies and the velocity
dispersion profile of the Brightest Cluster Galaxy (BCG), obtained from
VIMOS@VLT and MUSE@VLT data. We solve the Jeans equation of dynamical
equilibrium using an upgraded version of the MAMPOSSt method. The total mass
profile is modeled as a sum of a generalized-NFW profile that describes the DM
component, allowing for a free inner slope of the density profile, a Jaffe
profile that describes the BCG stellar mass component, and a non-parametric
baryonic profile that describes the sum of the remaining galaxy stellar mass
and of the hot intra-cluster gas mass. Our total mass profile is in remarkable
agreement with independent determinations based on X-ray observations and
strong lensing. We find gammaDM=0.7 -0.1 +0.2 (68% confidence levels),
consistent with predictions from recent LambdaCDM cosmological numerical
simulations.Comment: Submitted to ApJ on June, 1st 2023. 14 pages, 9 figure
- …